What brand / model of pump did you use? Is there a reason that I would not want to use a larger pump?
Submerged pumps generally all use Franklin motors attached to the various manufacturers heads.(Jackussi Groundfoss etc) and the number of impellers make up the GPMs and lift capabilities.
The pump manufacturers have very detailed charts as to the specs of their pumps. (Lift GPM etc)
Google water well pumps should take you to manufacturers sites with all specs and graphs.
In my system I have a standard bladder tank installed as it is also my whole house system with the watering simply tied in. This way I have a constant 60 PSI at the sprinklers 200ft away uphill. I have run 3 sprinklers at a time no problem.
If you do use a submerged well pump be sure to cage it with large area of screening to prevent ingestion of debris* and try to have it as vertical as possible** as they are designed to be hung in the wells. A check valve is a must at the pump. (some have built in)
*Sand is the big enemy as it can destroy the impellers.
** We generally weld up a rack that positions the pump at about a 60 deg angle.
A pump can only pull one atmosphere (30 odd ft) but can push a whole lot more (depending on pressure).
Jet pumps pull 30 ft and then push back down via an injector to push water back up to higher 'lifts'.
Downside is the tricky primeing to get the system operating and the absolute need for no leakage at all and that is not counting of the double pipe runs needed.
Seasonal usage then calls for annual drainage and primeing.
Time has proven that the only sure drainage is to use a compressor to blow all lines clear and naturally that means re connecting all fittings every year.
For that reason all our lakeside dwellings now use submerged pumps.
My trick is to install a 'T' under water with a ball valve in the side leg so that when I open the valve gravity drains the system for me.
With all taps open in the house the down rush of water sucks the lines taps etc dry.
Naturally hot water and pressure tanks get drained as well.
Come spring simply closing that ball valve and power the pump and everything is good to go.